All posts tagged Problem Solving

Some of you may be aware that crows (who are corvids, like magpies and Clark’s Nutcrackers) are excellent problem solvers and that they are one of the few birds known to engage in tool use.

While there have been a variety of popular press articles describing tool use by New Caledonian crows, in this post I wanted to showcase a few videos that demonstrate visually just how impressive these crows are.

The first video features a New Caledonian crow creating a bent wire hook to fish out a food treat after realizing that a straight piece of wire won’t do the trick. Check it out; it’s pretty incredible:

…

In a second demonstration of cognitive abilities, the crow employs a sequence of three tools to obtain food reward – using a short stick to withdraw a medium-length stick, using the medium-length stick to obtain a long stick, and then using the long stick to reach the food. As the video notes, this is the first time a non-human animal with no explicit training has been observed using three different tools in the correct sequence to achieve a goal. Again, the video illustrates this feat quite nicely:

…

Finally, a recent Wired1 article, together with accompanying video, features a New Caledonian crow finding a novel use for a tool, poking a rubber spider. This sort of flexible tool use is quite rare, and crows are the first non-mammals who have demonstrated that they can use a single tool in multiple ways. Here’s the video:

…

I love how the crow gingerly pokes at the rubber spider and then jumps back – talk about a a familiar looking reaction!

For more information and videos relating to tool usage by New Caledonian crows, you can explore the tool use website2 of the Behavioural Ecology Research Group at the University of Oxford.

I wanted to devote today’s post to a wonderful presentation on cephalopods that Maggie Koerth-Baker, the Science Editor at BoingBoing.net, gave last January at the University of New Mexico’s annual conference on Integrating Nanotechnology with Cell Biology and Neuroscience.

There is also a 10-minute edited version of the presentation, which you can find here, but I highly recommend spending half an hour to take in the full video (below), since many of the really fascinating stories have been edited out of the shorter version.

There are parts of Koerth-Baker’s presentation that I just love, particularly how she addresses the question of how we define intelligence. As she puts it (and this part isn’t contained in the edited version):

Intelligence is a loaded word. What does intelligence mean to you? IQ tests, grade point average, the ability to communicate via spoken language?

One thing is certain: “intelligence” makes us think of human stuff, people things. And that’s not fair.

An octopus doesn’t need to be able to pass a written exam. It never has. To judge animals against human ideas of what intelligence means in humans is to miss the point of evolution. Our brains are not this private club that the rest of animal-kind is trying to be cool enough to get into. Every species has adapted over millions of years to have a brain that allows it to be smart for its particular niche.

Octopus brains can get octopus jobs done, and they don’t have to worry about whether they can tackle human issues. Your octopus will not do your homework, but that doesn’t mean it’s stupid.

Later, she adds:

It is absolutely true that there is something very different, and very exciting, going on in the cephalopod brain, especially when you consider its nearest relatives. Cephalopods are closely related to mollusks, and their family reunion would feature such dignitaries as snails and oysters.

A layman might go ahead and call it “intelligence.” I’m just going to call it “being awesome.”

These are not big brained creatures. They can’t navigate a maze like a cephalopod can. They can’t react quickly and change their behavior to reflect minute by minute changes in their environment. And, with a couple of notable exceptions, they don’t seem to be able to remember information and use it in the future.

In the nature and in the lab, invertebrate cephalopods act more like vertebrates. Researchers describe this special class of conduct as “behavior plasticity” or “behavioral flexibility.” A layman might go ahead and call it “intelligence.” I’m just going to call it “being awesome.”

The full presentation goes on to illustrate various “awesome” abilities of the cephalopods, including decision-making, arguable tool use, and communication with other cephalopods. Koerth-Baker also provides a vivid example of how an octopus will engage in highly sophisticated mental processes in executing tactics to escape predators. When faced by a researcher perceived to be attacking:

an octopus would swim backwards away from [the researcher] toward handy places where it could hide. When it got to one of these spots, the octopus would squirt out a jet of ink in one direction, and dive away in the opposite direction, immediately changing its camouflage to match its new hidey-hole. Basically, it was giving him the old dodge and feint routine.

Now, think about everything an octopus had to do to process that. While swimming for its life, it had to know where [the researcher] was and where the next hidey holes were. It had to think about the timing to trick [the researcher] with the ink squirt. And it had to know what color and texture to turn its skin as it dove away. All of that pretty much at the same time. That’s broad awareness and complex decision-making, done at high speeds by a creature with a mollusk brain.

Verdict: awesome.

Indeed.

It really is thought provoking to consider the concept of intelligence, particularly in animals that are so different than we are. The latter part of the video provides an overview of the octopus brain and neural anatomy – if you think you know how a brain generally looks and functions (or should look and function), you will find this segment to be eye opening.

So, how intelligent are the cephalopods? They can’t read or write, they can’t speak, they aren’t particularly social. Their brains, while larger than any other invertebrate’s (and comparable in size to the brains of dogs and cats), are nowhere near the size of human brains, and cephalopods don’t exhibit many of the higher cognitive functions that we test when we measure human intelligence. Their SAT scores would undoubtedly be unimpressive.

On the other hand, how would we humans do on an octopus intelligence test, one that required us to consciously change our shapes, colors, textures and brightness in order to adapt to threats and changing environmental conditions? Cephalopods have incredible mental abilities that we are totally lacking – what does this say about whether those mental abilities are, or are not, evidence of intelligence?

These are hard questions, but one point should be pretty clear. Octopuses are awesome.

I have bad news for you – a pigeon can probably outperform you in the area of probability and statistics. Yes, that’s right, a pigeon.

The Problem:

Consider the classic “Monty Hall” problem, named after the original host of the Let’s Make a Deal game show:

Suppose you’re on a game show and are given the choice of three doors. Behind one door is a car; behind the others, goats. The car and the goats were placed randomly behind the doors before the show. Before opening the door you’ve picked, the host, who knows what’s behind the doors, must open one of the remaining doors and make you an offer. Accordingly, he opens a door, reveals a goat, and asks you whether you want to stay with your first choice or switch to the last remaining door.

Assuming you want a car and not a playful goat, should you stick with your first choice or go for the remaining door?

The Answer:

This may sound counterintuitive (unless you’re a pigeon), but you actually have twice the chance of winning the car if you change your selection and pick the remaining door. Why is this? Well, the relevant Wikipedia1 entry includes the following table, which shows the three possible arrangements of one car and two goats behind three doors and the result of switching or staying after initially picking Door 1 in each case:

Door 1

Door 2

Door 3

Result if switching

Result if staying

Car

Goat

Goat

Goat

Car

Goat

Car

Goat

Car

Goat

Goat

Goat

Car

Car

Goat

As shown above, a player who stays with the initial Door 1 choice wins in only one out of three of these equally likely possibilities, while a player who switches wins in two out of three.

How Do People Perform?

In a word, poorly.

Most people will stay with their initial choice or, at best, express no preference either way. In one high profile case, Marilyn Vos Savant (she of the world’s highest IQ) published the answer to the puzzle in Parade magazine and approximately 10,000 readers, including nearly 1,000 with Ph.D.’s, wrote in to vehemently claim she was wrong. The New York Times2 published a fuller explanation of the Monty Hall problem as well as an entertaining account of the Vos Savant incident and how a large number of mathematicians and other well-educated people refused to accept the correct answer, even after being shown multiple proofs of its accuracy.

How Do Pigeons Perform?

Much better!

As published in the Journal of Comparative Psychology3, researchers Walter Herbranson and Julia Schroeder designed a series of experiments in which six pigeons were tested to see how well they would do at solving the Monty Hall problem, and how their performance would compare to that of university undergraduate students. Discover Magazine’s Not Exactly Rocket Science4 blog describes the experiments and the results:

Each pigeon was faced with three lit keys, one of which could be pecked for food. At the first peck, all three keys switched off and after a second, two came back on including the bird’s first choice. The computer, playing the part of Monty Hall, had selected one of the unpecked keys to deactivate. If the pigeon pecked the right key of the remaining two, it earned some grain. On the first day of testing, the pigeons switched on just a third of the trials. But after a month, all six birds switched almost every time, earning virtually the maximum grainy reward.

Every tasty reward would reinforce the pigeon’s behaviour, so if it got a meal twice as often when it switched, you’d expect it to soon learn to switch. Hebranson and Schroder demonstrated this with a cunning variant of the Monty Hall Dilemma, where the best strategy would be to stick every time. With these altered probabilities, the pigeons eventually learned the topsy-turvy tactic.

It may seem obvious that one should choose the strategy that would yield the most frequent rewards and even the dimmest pigeon should pick up the right tactic after a month of training. But try telling that to students. Hebranson and Schroder presented 13 students with a similar set-up to the pigeons. There were limited instructions and no framing storyline – just three lit keys and a goal to earn as many points as possible. They had to work out what was going on through trial and error and they had 200 goes at guessing the right key over the course of a month.

At first, they were equally likely to switch or stay. By the final trial, they were still only switching on two thirds of the trials. They had edged towards the right strategy but they were a long way from the ideal approach of the pigeons. And by the end of the study, they were showing no signs of further improvement.

In their article, Herbranson and Schroeder summarized the results even more succinctly: “The surprising implication is that pigeons seem to solve the puzzle, arriving at the optimal solution while most humans do not.”

Conclusion

While we will accept the view of the researchers that this doesn’t prove that pigeons are smarter than humans, we still think that, if you ever have a chance to appear on Let’s Make a Deal, you should consider bringing a real bird rather than a friend dressed up in a giant bird costume.